Pfizer Inc.'s Revatio Gets European OK For Rare Disease
NEW YORK, Nov. 4 /PRNewswire-FirstCall/ -- Pfizer Inc said today that the European Medicines Agency (EMEA) has approved Revatio(TM) (sildenafil citrate) for the treatment of pulmonary arterial hypertension (PAH), a rare, aggressive and life-shortening vascular disease. Sildenafil citrate is the active ingredient in Viagra®, Pfizer's erectile dysfunction medication, which has been used by more than 27 million men worldwide.
PAH is a blood vessel disorder of the lungs in which pressure in the pulmonary artery rises above normal levels. The pulmonary artery carries blood from the right ventricle in the heart to small arteries in the lungs. Increased pressure causes the walls of these arteries to tighten, decreasing blood flow, along with thickening of the pulmonary artery walls. The lack of oxygen-rich blood causes fatigue and breathlessness in patients. Left untreated, the condition can cause death. PAH affects approximately 100,000 people worldwide and is seen most commonly in women between the ages of 20 and 40.
"The company is pleased with the European regulatory decision and looks forward to making Revatio available to patients in all member states of the European Union, said Michael Berelowitz, Pfizer Vice President Worldwide Medical. "Pfizer's six-year clinical program for Revatio demonstrates our continuing commitment to develop medications for unmet medical conditions, including those that affect small numbers of patients."
Revatio is classified by the EMEA as an orphan drug. Medicines granted orphan drug status are intended for rare and serious or life-threatening diseases that affect fewer than five in 10,000 persons, or are medicines unlikely to be developed under normal market conditions.
Revatio was approved for the treatment of patients with PAH classified as WHO functional class III, to improve exercise capacity. Efficacy has been shown in primary pulmonary hypertension and pulmonary hypertension associated with connective tissue disease.
The EMEA approval was based on the results of a double-blind, placebo- controlled study of 278 patients with PAH. Patients were randomized to three different dosages of Revatio (20 mg, 40 mg, or 80 mg) three times a day or placebo. All three treatment groups showed statistically significant improvements in the primary endpoint of six-minute walk distance. No significant differences were observed between the three dosages in six-minute walk distance, thus the approved dose is limited to 20 mg three times daily. Patients taking Revatio also showed statistically significant improvements in other important measures of cardiac function.
Patients were followed for an additional year as part of an open-label extension trial. Improvements in walk distance and cardiac function were preserved, with Revatio patients showing a 96 percent survival rate, compared to an expected survival rate of 71 percent.
Revatio was generally well tolerated at all doses. The most common side effects were similar to the established safety profile of Viagra used for the treatment of erectile dysfunction, including headache, dyspepsia, flushing, epistaxis, and insomnia.
The use of Revatio or Viagra and organic nitrates in any form, at any time, is contraindicated.
Revatio will be distributed as a white, round 20mg pill to distinguish it from Viagra's blue diamond-shaped pill for erectile dysfunction.
Revatio was approved for the treatment of PAH by the United States Food and Drug Administration in June of 2005.
Source: Pfizer Inc